Tamibarotene is a synthetic retinoid presently approved in Japan for the treatment of APL, and in US, Europe and China it is still under development for APL. Compared to other retinoid drugs available, Tamibarotene has not just a higher activity as a retinoid, but also shows a higher receptor selectivity towards the Retinoic Acid Receptor (RAR) subtypes alfa and beta, but not gamma. All trans retinoic acid (ATRA) and its derivatives are usually pan-agonists to these subtypes, and often are know for the irritation to the skin as one of their major side effects which is due to the RAR gamma subtype. Moreover, unlike ATRA tamibarotene does not cause induction of drug metabolism by CRABP.